<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
	<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
	<title>Document</title>
</head>
<body>
	<form action="0.1.php" method="post">
		第一个数字：<input type="text" name="username1"/>  
		运算符：<input type="text"  name="num1" /> 
		第二个数字：<input type="text" name="username2"/> <button>提交</button>
	</form>
</body>
</html>